1. Field of the Invention
This invention relates generally to the process of opening mollusk shells and more particularly to the opening of oyster shells so as to obtain access to the oyster inside.
2. General Background
It is fully recognized that the hinged shell surrounding the oyster or clam is an effective protection mechanism and is very difficult to open due to the strong muscle tissue which holds the two halves of the shell together. Never the less, humans and animals alike have been dining on these crustaceans for centuries using only simple tools. However, man has continuously sought to improve his efficiency for removal of the oyster shell.
Oyster shucking, the process of opening and removing of oysters from their shell, can be divided into three distinct groups: Manually opening, by prying the shell apart with a shape tool, various semi-manual apparatus for holding, notching and spreading the shells apart and includes methods for cutting the adductor muscle, and, finally, the fully automatic apparatus for cutting the shell, separating and removing the oyster on a production basis.
The semi-manual apparatus well known within the art demonstrates that the oyster or clam shell can be positioned against a movable or stationary anvil and a fixed or movable wedge shaped instrument forcibly inserted in the seam between the two halves, thereby prying the shells apart. However, such apparatus require a good deal of force to separate the shells sufficiently to break the hinge and tear the adductor muscle. Therefore, a pivotal lever is generally employed. In other apparatus the shells are simply separated a minimal distance to allow for cutting the adductor muscle, thus allowing the oyster or clam to be removed from the shell by hand. The method for separating the shell may utilize a motorized combination of a wedge and rotatable blade to pry the shell apart while being held in position by hand, a hazardous operation at best.
With the exception of the fully automatic, production operations, which are generally cumbersome, expensive and generally require further handling, the various shucking apparatus require that the oyster be positioned in or on an anvil member and a wedge of some sort be placed in contact with the natural seam opening in the oyster shell. A force is applied manually or by pivotal leverage and or rotation of the wedge within the seam, thus forcing the shells apart. Since no two oysters are the same size or exact configuration, such procedures require a good deal of manual exertion and dexterity to become efficient. It is therefore desirable to remove the oyster from the shell as efficiently and as safely as possible. However, most such manual extraction apparatus have proven to be either ineffective, hard to use, or hazardous to personnel. Accordingly, a more efficient, less demanding apparatus for this purpose is highly desirable.